Exercise and Immune System | How to Support Your Immune System – Runner’s World
There’s nothing quite as devastating as showing up to your race feeling sick and unmotivated to do the one thing you’ve spent months training for.
Whether you’re a seasoned runner or gearing up for your first race, no matter the distance, catching a cold just before you compete can have a detrimental influence on your mental stamina and confidence. Not to mention, your physical ability—arriving at the start line feeling sniffly and fatigued isn’t exactly an ideal condition for securing a personal record, though it can be done.
This has personally happened to me before. When I ran the 5K for high school cross- country, I always seemed to catch a cold during the final weeks of the season, inconveniently right before the championship meets. Now, over 10 years later as a marathoner, I continue to hear runners vent about getting a cold just before or right after their race.
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So, what is it about the week or two leading up to a race that appears to make runners more susceptible to illness? Is there scientific evidence to even back this theory up or is it largely psychological? Or, worse—is this unspoken annoyance among the running community just bad luck and unrelated to tapering?
The truth is, there isn’t much research out there that explores what happens to the immune system as you begin to taper, or back off on miles, for a race of any distance. This doesn’t come as a surprise—after all, it is very specific! However, research does indicate that exercising regularly can by fostering an anti-inflammatory environment in the body, which can help it fend off infection.
So if maintaining a consistent running schedule can potentially strengthen your immune system, it begs the question of whether a significant drop in mileage can then begin to weaken your immune system, right?
To come to the bottom of this debate, we turned to the experts to deliver the facts.
First of all, can training for a race actually strengthen your immune system?
“Running and other forms of exercise have a positive effect on your immune system,” says , M.D., a board-certified preventive medicine physician, health expert, and fitness professional. “Research shows that exercise causes an anti-inflammatory response and an increase in the number and activity of immune cells.”
However, as , M.S., R.D.N, at Greene Health, points out that running too much—or overtraining—can, in some cases, elicit the opposite effect. She adds that determining whether or not running has a positive effect on the immune system may also depend on the intensity and duration of the run.
“ that running with moderate exertion levels for less than 60 minutes can have a positive effect on immunity,” Greene says. “Exercising in this way can lower inflammation and improve glucose [sugar] and lipid [fat] metabolism.”
But for those who are going the extra distance and training for half marathons or marathons, running at this intensity for months on end could potentially pose a hindrance to immune function.
“The combination of training workloads and the physiological and psychological stress that goes along with them can actually lead to immune dysfunction and inflammation,” she says.
When a runner begins to taper, what might happen to their immune system?
The answer doesn’t have to do with the decrease in mileage at all.
Apart from being around someone who is sick, the likelihood of coming down with something may depend on how you respond to big events. For example, if you’re someone who gets anxious or overly stressed about a week or two leading up to the race, it’s possible you’re more susceptible to catching something than someone who’s a bit more relaxed.
“We all know that feeling. You’re a few days away from a race and your adrenaline is at a steady high. The excitement and nervous energy can make it hard to sleep and eat,” says Greene. “This, unfortunately, is a recipe for getting sick.”
Remember, the research above suggests that running long distances for a prolonged period of time may actually weaken the immune system.
“Couple a weakened immune system with psychological stress and you become more susceptible to getting sick,” says Greene.
Calder argues that cutting back on miles may even be beneficial for immune function.
“Moderate-intensity exercise seems to be helpful to the immune system,” she says. “If anything, cutting back may be helpful if a runner has been training intensively and vigorously with little recovery time.”
What are some ways you can support your immune system as you taper so that you’re healthy for the race—and the days following?
While trying to prevent sickness feels a bit uncontrollable, there are several, not-so-obvious ways you can set your immune system up for success in the event you encounter someone who is ill before race day.
Aside from eating plenty of antioxidant-rich fruits and vegetables, and taking and , you should also consider…
1. Taking a B complex with iron or a multivitamin
“Nutrition needs are increased for endurance runners and sometimes it can be difficult to keep up with demands through diet alone,” says Greene. “B vitamins and iron are critical for energy support and recovery. If you are someone who meets your caloric needs but does not consume a variety [of foods], try a multivitamin.”
Pro tip: Greene adds that it’s imperative to make sure the supplements you choose are .
2. Consuming enough protein each day
“Runners typically have no problem getting enough carbohydrates, but when it comes to protein, you do not want to skimp on this macronutrient,” says Greene. “Protein is a fundamental part of an optimal immune system—it is wise to consume at least 1.2 to 2 grams/kg of body weight.”
3. Including fermented foods like kimchi, kefir, and sauerkraut into your diet to support gut health
“Good bacteria [probiotics] in the gut can create a barrier to pathogens preventing illness,” says Greene. “In addition, consuming more probiotics from food can support immunity from illnesses like diarrhea and possibly upper respiratory infections.”
4. Making it a priority to get enough quality sleep
Calder emphasizes that getting adequate sleep is important for a healthy immune system, adding that adults should aim for about 7 to 9 hours per night.
5. Incorporating rest days into your training cycle, before tapering begins
“Allow yourself rest days in your training schedule to allow your body a recovery period,” says Calder. “Intense training without proper rest may have a negative effect on your immune system.”
The Bottom Line
If you’re someone who tends to get anxious or stressed as you’re tapering, you may be more likely to get sick by the time of your race. This may especially be the case if your stress levels are causing you to miss out on sleep and nutritious meals. Thankfully, there are several ways you can bolster your immune system during this time—and while you’re in the thick of your training season—so you show up to race day healthy.
Though, when it comes to COVID-19 and its variants, the best way to protect yourself from severe illness is to and subsequent booster shots.
Cheyenne Buckingham is a health writer and editor, specializing in content related to nutrition, fitness, chronic disease, mental health, and women’s health, among other topics. She’s also an avid long distance runner.